Commonly, siding, decking, fencing, or roofing nails and other fasteners intended for outdoor use or other exterior applications are made from carbon steel wire. It is necessary to protect such fasteners against corrosion.
It is conventional to galvanize such fasteners, in a batch process, after such fasteners have been formed. It is known, moreover, to coat the galvanized nails with a polymeric material, which provides further protection against corrosion.
As disclosed in Lat et al. U.S. Pat. No. 5,033,181, it is known to make such fasteners from carbon steel wire coated with a protective, metallic layer having corrosion-resistant properties, such as pre-galvanized, carbon steel wire or pre-chromated, carbon steel wire. As disclosed therein, the protective, metallic layer is discontinuous and the carbon steel of the wire is exposed at a region on a leading end of the wire, on which end a head of such a fastener is formed.
As disclosed in the Lat et al. patent, the head of each fastener is coated with a protective, polymeric layer covering the region where the protective, metallic layer is discontinuous, so as to restore the corrosion-resistant properties of such fastener.